Training ammunition for mortars



Oct. 4, 1966 -R ETAL TRAINING AMMUNITION FOR MORTARS Filed Aug. 12, 1964IIII N MQ 5 N E R A a Y mR W R WH 0 3 mm w n WMAS 4. \.S 1 E Z mmm ACLUHHRQ United States Patent 3,276,374 TRAINING AMIVIUNITION FOR MORTARSHans Stadler, Nurnberg, and Heinz Gawlick and Rudolf Stahlmann, Furth,Germany, assignors to Dynamlt Nobel Aktiengesellschaft, Troisdorf,Germany Filed Aug. 12, 1964, Ser. No. 408,710 Claims priority,application Germany, Aug. 13, 1963, 1) 42,232 Claims. (Cl. 102-41) Thepresent invention relates to a practice or training ammunition formortars. Such practice or training ammunition is already known per se.An inset barrel is built into a dummy shell which corresponds in itsdimensions to the live ammunition; a small-caliber practice grenade canbe loaded into and fired from the inset barrel. The dummy shell therebyrepresents the carrier or support of the inset barrel Which has to bepulled out of the barrel after each firing of the small-caliber traininggrenade and has to be reloaded for further use. This is possible Withoutdifficulties with breech loaders since the dummy shell together withinset barrel can be readily pulled out of the barrel toward the rear.

However, if muzzle loaders are involved as are currently in use formortars, then pulling out the dummy shell together with the inset barrelbecomes dilficult as it has to take place from in front of the barrelmouth. It has already been proposed to secure a pull cord at the mortardummy shell and to pull out the fired dummy with the aid of this pullcord. That this type of unloading of the mortar is complicated andunfavorable for the firing speed required also during training orpractice firing is obvious.

Accordingly, :a practice ammunition has been develo ed for mortars ofthe type now designated by Morser, which also permits rapid firing. Thispractice ammunition comprises a dummy shell in the form of a live mortarshell which contains an axial inset barrel for a smallcaliber practiceshell in the form of a reduced mortar shell. A propellant charge for thesmall-caliber shell is located rearwardly in the inset barrel, and anejector charge is seated in the tail piece of the dummy shell.

During loading of the mortar by letting the dummy shell fall into themortar barrel, both the ejector charge which burns with delay as Well asalso the propellant charge for small-caliber training grenade in theinset barrel are ignited upon impact of the practice ammunition with thebarrel bottom. The propellant charge for the small-caliber practiceammunition burns without delay and propels the training grenadeforwardly through the inset barrel, then through the mortar barrel tothe target. In the meantime, the ejector charge burns with delay andejects the dummy shell together with the inset barrel out of the mortarbarrel in the forward direction. The ejector charge is so dimensionedthat the gases thereof set the dummy shell into motion only when thepractice shell already is in free flight.

The present invention aims at a simplification of this known trainingammunition and at a safe ignition thereof.

For this purpose, with the new and improved training ammunition formortars in accordance with the present invention in which an insetbarrel for a small-caliber training grenade is seated within a shelldummy and in which an ejector charge is located in the tail piece of thedummy within a cartridge case that is ignited during loading of themortar, whereby the firing of the practice grenade or shell takes placeduring the movement of the dummy shell in the mortar barrel, accordingto the present invention there is securely arranged on the caseaccommodating the ejector charge an ignition pin while the practicecartridge is slidably supported within the inset barrel so as to beslidable in the rearward direction and 3,276,374 Patented Oct. 4, 1966is seated against a bell-shaped inertia sleeve, springloaded in theforward direction by a retaining spring, whose return stroke during thefiring jolt is so dimensioned and matched to the dummy shell that theignition pin penetrates during the firing through the bell-shapedinertia sleeve and pierces the primer or percussion cap of thepropellant charge in the training shell cartridge.

Accordingly it is an object of the present invention to provide atraining ammunition, particularly for mortars, which obviates thedrawbacks and inconveniences encountered with the prior artconstructions 'by simple, com: pact and operationally reliable means.

It is another object of the present invention to provide a trainingammunition, particularly for mortars, which not only facilitates loadingbut to an even greater extent unloading of the mortars without impairingrapid firing.

Still another object of the present invention resides in the provisionof a training ammunition, especially for mortars, which achieves theaforementioned advantages in conjunction with a safe and reliableignition.

These and other objects, features, and advantages of the presentinvention will become more obvious from the following description whentaken in connection with the accompanying drawing which shows, forpurposes of illustration only, one embodiment in accordance with thepresent invention, and wherein the single figure is a centerlongitudinal cross sectional view through the tail piece of the dummyshell of the training ammunition in accordance with the presentinvention.

Referring now to the single figure of the drawing, reference numeral 10designates therein the tail piece of a mortar shell dummy which isprovided with an axial longitudinal bore as inset barrel for thesmall-caliber grenade or shell 13. The small-oaliber grenade or shell 13is seated in the cartridge case 12 which includes the usual primer orpercussion cap 14 for igniting the propellant charge disposed in thecartridge case 12. The cartridge chamber of the inset barrel 11 is sodimensioned that the cartridge 12, 13 of the practice grenade or shellis able to slide in the backward direction within the same.

The training shell or practice grenade cartridge 12, 13, is seated withthe bottom 15 thereof against the forward portion of a bell-shapedinertia sleeve 16 which is slidably disposed within a breech casing 17.The breech casing 17 is provided in the forward portion thereof withlocking cams which are threaded into an interrupted thread-as withinterrupted-screw-type breech locks-that are provided in the rearportion of the tail piece 10 of the dummy shell. After unscrewing thebreech casing 17 the inset barrel 11 may be loaded with the trainingcartridge 12, 13. The bell-shaped inertia sleeve 16 thus forms a type ofmovable impact bottom.

To the rear a bottom cap 18 is threadably inserted into the breechcasing 17 into which is inserted from the rear the ejector chargecartridge 19 which, in turn, is secured by means of a screw cap 21. Theejector charge cartridge 19 carries in the bottom thereof a primer orpercussion cap 20. To the rear of the primer 20, the screw cap 21 isprovided with a bottom aperture for the ignition pin securely seated onthe mortar barrel bottom as is known with mortars. Gas dischargeapertures are accommodated within the walls of the bottom cap 18 for theescape of the ejector gases causing the ejection of the dummy.

A fixed ignition pin 22 is seated coaxially on the front end of thebottom cap 18 which ignition pin 22 is surrounded by a retainer spring23 that keeps the bell-shaped inertia sleeve 16 pressed against thebottom of the training grenade cartridge 12, 13.

OPERATION The described practice ammunition operates as follows: Afterunscrewing the breech casing 17 out of the end of the tail piece of thedummy shell the training cartridge 12, 13 is loaded into the insetbarrel 11 whereupon the inset barrel 11 is closed again by threadablyreassembling the breech casing 17. The cartridge 12, 13 is then heldsecurely in place by the spring loaded fell-shaped inertia sleeve 16.Subsequently, the ejector charge cartridge 19 is inserted into thebottom cap 18 and is secured therein by means of the screw cap 21. Theshell dummy is then loaded or armed.

For purposes of firing, the thus loaded shell dummy is inserted into themortar barrel from in front thereof. It impinges against the bottom ofthe mortar barrel whose fixed ignition pin punctures through theaperture in the screw cap 21 to strike the primer or percussion cap 20that in turn ignites the ejector charge 19. The propellant gasesdeveloped by the ejector charge 19 escape through the wall apertures ofthe bottom cap 18 into the mortar barrel to the rear of the dummy shelland commence the forward movement thereof. As a result of the firingjolt or shock occurring thereby the bell-shaped inertia sleeve 16 andtogether therewith the training grenade cartridge 12, 13 slidebackwardly within the inset barrel 11. The primer or percussion cap 14in the bottom of the training grenade cartridge 13, 12 is therebypierced by the fixed ignition pin 22 and thereby ignites the propellantcharge for the practice grenade in the cartridge 12 of the grenadecartridge. Since the propellant charge burns faster than the ejectorcharge, the small-caliber practice grenade is propelled forwardlythrough the inset barrel 11 into and through the mortar barrel. The moreslowly burning ejector charge then develops so much propellant gas thatthe dummy shell is ejected forwardly out of the mortar barrel.

The ejector charge is so selected that the dummy falls to the groundalready in the proximity to the barrel mouth.

While we have shown and described one embodiment in accordance with thepresent invention, it is understood that the same is not limited theretobut is susceptible of numerous changes and modifications as known to aperson skilled in the art, and we therefore do not wish to be limited tothe details shown and described herein but intend to cover all suchchanges and modifications as are encompassed by the scope of theappended claims.

We claim:

1. A practice ammunition, prising:

a dummy shell including a tail piece and provided with inset barrelmeans for a small-caliber practice shell,

a casing means for accommodating therein an ejector charge and securedat said tail piece,

ignition pin means securely arranged at the forward end of said casingmeans,

a practice shell within said inset barrel means having a propellantcharge,

and means for supporting said practice shell within said inset barrelmeans in such a manner as to be slidable in the rearward direction toenable ignition of the propellant charge of the practice shell by saidignition pin means during the shell upon firing of said dummy shell.

2. A practice ammunition, especially for mortars, comprising:

a dummy shell including a tail piece and provided with inset barrelmeans for a small-caliber practice shell, casing means for accommodatingtherein an ejector charge and secured at said tail piece,

ignition pin means securely arranged at the forward end of said casingmeans,

a practice shell within said inset barrel means having a propellantcharge and-primer means in the bottom portion thereof for igniting saidpropellant charge, and supporting means for supporting said practiceshell within said inset barrel means to be slidable in the especiallyfor mortars, comrearward stroke of the practice 4 rearward direction fora rearward stroke sufficiently long that the ignition pin pierces theprimer means to enable ignition of the propellant charge of the practiceshell during the rearward inertia stroke of the practice shell uponfiring of said dummy shell.

3. A practice ammunition, especially for mortars, comprising:

a dummy shell including a tail piece and provided with inset barrelmeans for a small-caliber practice shell, casing means for accommodatingtherein an ejector charge and secured at said tail piece,

ignition pin means securely arranged at the forward end of said casingmeans, a practice shell within said inset barrel means having apropellant charge,

and means for supporting said practice shell within said inset barrelmeans in such a manner as to be slidable in the rearward direction toenable ignition of the propellant charge of the practice shell by saidignition pin means during the rearward stroke of the practice shell uponfiring of said dummy shell including bell-shaped inertia sleeve means onwhich said practice shell is seated, spring means normally urging saidsleeve means in the forward direction into engagement with the bottom ofthe practice shell.

4. A practice ammunition, especially for mortars, comprising:

a dummy shell including a tail piece and provided with inset barrelmeans for a small-caliber practice shell, casing means for accommodatingtherein an ejector charge and secured at said tail piece,

ignition pin means securely arranged at the forward end of said casingmeans, a practice shell within said inset barrel means having apropellant charge and primer means in the bottom portion thereof forigniting said propellant charge,

and supporting means for supporting said practice shell within saidinset barrel means to be slidable in the rearward direction for arearward stroke sufficiently long that the ignition pin means piercesthe primer means to enable ignition of the propellant charge of thepractice shell during the rearward inertia stroke of the practice shellupon firing of said dummy shell including bell-shaped inertia sleevemeans on which said practice shell is seated, spring means normallyurging said sleeve means in the forward direction into engagement withthe bottom of the pnactice shell.

5. A practice ammunition, especially for mortar, comprising a dummyshell having an axially extending barrel for a small calibre practiceshell; a casing releasably secured to the rearward end of said dummyshell and having an ejector charge at its rearward end; a forwardlypointing ignition pin rigidly attached to the forward end of said casingand axially aligned with said axially extending barrel; a practice shellwithin said axially extending barrel having a propellant charge andprimer means in the rearward portion axially aligned with said ignitionpin for igniting said propellant charge; means for supporting saidpractice shell within said barrel for limited axial movement relative tosaid barrel in the rearward direction from the forward position for adistance greater than the axial distance between said ignition pin andsaid primer means; positioning means normally holding said practiceshell in the forward position against said rigid stop abutment means andbeing ineffective to hold said practice shell in the forward positionagainst the inertia forces of said practice shell produced by the firingof said dummy shell ejector charge operable to enable ignition of theprimer means and propellant charge of the practice shell 'by saidignition pin means during the rearward axial movement of said practiceshell upon firing of said dummy shell.

6. The practice ammunition of claim 5, wherein said positioning meansresiliently urges said practice shell in the forward direction.

7. The device of claim 6, wherein said casing has a plurality oftransversely extending aperture means operable to conduct the combustiongases of said ejector charge outside of said casing without damagingsaid casing so that said casing may be reused.

8. The device of claim 6, including a screw cap releasably secured tothe rearward end of said casing to hold the ejector charge in saidcasing and having an axially extending bore for the passage of themortar firing pin for igniting said ejector charge and said casinghaving wall means for removal and replacement of said ejector chargewhen said screw cap is removed.

9. The device of claim 8, wherein said casing has a plurality of transversely extending aperture means operable to conduct the combustiongases of said ejector charge outside of said casing without damagingsaid casing so that said casing may be reused.

1b. The device of claim 5, wherein said positioning means includes arearwardly extending bell-shaped sleeve engaging the rearward end ofsaid practice shell having an axial bore aligned with said ignition pinand said primer means, and spring means resiliently urging saidbell-shaped sleeve and said practice shell in the forward direction.

11. The device of claim 10, including a screw cap releasably secured tothe rearward end of said casing to hold the ejector charge in saidcasing and having an axially extending bore for the passage of themortar firing pin for igniting said ejector charge, and said casinghaving wall means for removal and replacement of said ejector chargewhen said screw cap is removed.

12. The device of claim 11, wherein said casing has a plurality oftransversely extending aperture means operable to conduct the combustiongases of said ejector charge outside of said casing without damagingsaid casing so that said casing may be reused.

13. The device of claim 10, wherein said casing has a plurality oftransversely extending aperture means operable to conduct the combustiongases of said ejector charge outside of said casing without damagingsaid casing so that said casing may be reused.

14. The device of claim 10, wherein said propellant charge burnssubstantially faster than said ejector charge.

15. The device of claim 5, including a screw cap releasably secured tothe rearward end of said casing to hold the ejector charge in saidcasing and having an axially extending bore for the passage of themortar firing pin for igniting said ejector charge, and said casinghaving wall means for removal and replacement of said ejector chargewhen said screw cap is removed.

16. The device of claim 15, wherein said casing has a plurality oftransversely extending aperture means operable to conduct the combustiongases of said ejector charge outside of said casing without damagingsaid casing so that said casing may be reused.

17. The device of claim 15, wherein said propellant charge burnssubstantially faster than said ejector charge.

18. The device of claim 5, wherein said casing has a plurality oftransversely extending aperture means operable to conduct the combustiongases of said ejector charge outside of said casing without damagingsaid casing so that said casing may be reused.

19. The device of claim 18, wherein said propellant charge burnssubstantially faster than said ejector charge.

20. The device of claim 5, wherein said propellant charge burnssubstantially faster than said ejector charge.

References Cited by the Examiner UNITED STATES PATENTS 2,821,923 2/1958Alderson 102-49 3,094,934 6/1963 Anthony 102--41 FOREIGN PATENTS 66,9711/ 1940 Czechoslovakia.

BENJAMIN A. BORCHELT, Primary Examiner. R. F. STAHL, Assistant Examiner.

1. A PRACTICE AMMUNITION, ESPECIALLY FOR MORTARS, COMPRISING: A DUMMYSHELL INCLUDING A TAIL PIECE AND PROVIDED WITH INSET BARREL MEANS FOR ASMALL-CALIBER PRACTICE SHELL, A CASING MEANS FOR ACCOMMODATING THEREINAN EJECTOR CHARGE AND SECURED AT SAID TAIL PIECE, IGNITION PIN MEANSSECURELY ARRANGED AT THE FORWARD END OF SAID CASING MEANS, A PRACTICESHELL WITHIN SAID INSET BARREL MEANS HAVING A PROPELLANT CHARGE, ANDMEANS FOR SUPPORTING SAID PRACTICE SHELL WITHIN SAID INSET BARREL MEANSIN SUCH A MANNER AS TO BE SLIDABLE IN THE REARWARD DIRECTION TO ENABLEIGNITION OF THE PROPELLANT CHARGE OF THE PRACTICE SHELL BY SAID IGNITIONPIN MEANS DURING THE REARWARD STROKE OF THE PRACTICE SHELL UPON FIRINGOF SAID DUMMY SHELL.